TBL 3 - Pain Management and Analgesics Flashcards
What drugs are considered counterirritants?
Capsaicin, Menthol, Methyl Salicylate, and Camphor
What is the mechanism of counterirritants?
Desensitize thermal receptors (transient receptor potential vanilloid (TRPV)
What drugs are considered prostanoids?
Thromboxane, Prostaglandins, and Prostacyclin
What drugs use the COX-1 pathway?
Thromboxane and Prostaglandins
What drug uses the COX-2 pathway?
Prostacyclin
What drugs are considered corticosteroids?
Hydrocortisone, Prednisone, and Dexamethasone
What is the MOA of corticosteroids?
Inhibit phospholipase 2.
What is the MOA of acetaminophen (Tylenol)?
Unknown
What are the properties of acetaminophen (Tylenol)?
Analgesic
Antipyretic
Lacks anti-inflammatory properties
What is the role in therapy for acetaminophen (Tylenol)?
Opioid sparing
What is the adverse effect of acetaminophen (Tylenol)?
Hepatoxicity
What is the treatment for APAP/acetaminophen toxicity?
N-acetylcysteine (NAC)
What is the MOA of N-acetylcysteine?
Restores glutathione
What is the MOA of NSAIDs?
COX inhibitors
Inhibit prostanoid synthesis
What are some adverse effects of NSAIDs?
GL ulcers and bleeds
CV disease
Nephrotoxicity
Bleeding
Are NSAIDs anti-inflammatory?
Yes
What is an example of a COX-2 selective NSAID?
Celecoxib
What are some examples of Non-Selective NSAIDs?
Aspirin, Indomethacin, Meloxicam, Ibuprofen, Naproxen, Ketorolac, and Diclofenac
What are the three drugs that induce the “Triple Whammy?”
NSAIDs + Diuretics + ACE-is
Does aspirin reversibly or irreversibly bind COX enzymes?
Irreversibly
What are some toxic effects of aspirin?
Uncouples oxidative phosphorylation leading to metabolic acidosis.
Respiratory alkalosis -> respriratory acidosis.
What are some effects of aspirin toxicity?
Acidosis, tinnitus, bleeding, and altered mental status.
What is the treatment for aspirin toxicity?
Sodium bicarbonate
What are some examples of Alpha-2 Agonists?
Clonidine, Tizanidine, and Dexmedetomidine
What is the MOA of Alpha-2 Agonists?
Decreases presynaptic Ca2+ influx.
Increases postsynaptic K+ efflux.
What is the role in therapy for Alpha-2 Agonists?
Spasticity
What are some adverse effects of Alpha-2 Agonists?
Hypotension
Bradycardia
Sedation
What does Alpha-1 Agonism cause?
Constriction of vascular smooth muscle, leading to increased BP.
What does Alpha-2 Agonism cause?
Inhibits NE release from presynaptic neurons causing decreased BP and HR.
What are the MOA of TCAs?
Na+ channel blockers
Inhibit NE re-uptake
Inhibit serotonin (5-HT) re-uptake
Alpha-1 Antagonist
Anticholinergic
What are some examples of TCAs?
Amitriptyline, Nortriptyline, and Imipramine
What are the MOAs of Selective NE Re-Uptake Inhibitors (SNRIs)?
Inhibit the re-uptake of NE
Inhibit the re-uptake of 5-HT
What are some examples of SNRIs?
Venlafaxine and Duloxetime
What is the MOA of Selective Serotonin Re-Uptake Inhibitors (SSRIs)?
Inhibit the re-uptake of 5-HT
What are some examples of SSRIs?
Paroxetine, Fluoxetine, Citalopram, and Sertraline
How do you treat anticholinergic presentations caused by TCAs?
Primarily symptomatic +/- benzodiazepines.
Physostigmine
Pyridostigmine
How do you treat Na+ channel blockade caused by TCAs?
Sodium bicarbonate.
How do you treat Alpha-1 Antagonism caused by TCAs?
Fluids +/- vasopressors.
How do you treat Serotonin Syndrome caused by TCAs?
Primarily symptomatic +/- benzodiazepines
Cyproheptadine (serotonin antagonist)
What is the MOA of Sodium Channel Blockers?
Inhibits the neuron depolarization and action potential propagation leading to the inhibition of neurotransmitter release.
What are some examples of Sodium Channel Blockers?
Lidocaine and Carbamazepine
What is lidocaine used for?
Local anesthetic and opioid sparing.
What is an adverse effect of lidocaine?
Bradycardia
What is carbamazepine used for?
Trigeminal neuralgia
What are some adverse effects of carbamazepine?
Toxic epidermal necrolysis (TEN) and Steven Johnson Syndrome (SJS)
Bradycardia
SIADH: hyponatremia
CYP inducer
What is the MOA of GABA-B agonists?
Decrease presynaptic Ca2+ influx and increase postsynaptic K+ efflux
What is an example of a GABA-B agonist?
Baclofen
What is the role in therapy of GABA-B agonists?
Spasticity
What are some adverse effects of GABA-B agonists?
CNS depression
Abrupt withdrawal is associated with profound spasticity, hallucinations, fever, seizures, and hypertension.
What is the MOA of Calcium Channel Blockers?
Block presynaptic Ca2+ channels leading to a decrease in Ca2+ mediated neurotransmitter release from presynaptic neurons.
What are some examples Calcium Channel Blockers?
Gabapentin and Pregabalin
What are the roles in therapy of Calcium Channel Blockers?
Neuropathic pain from diabetes
Fibromyalgia
Opioid sparing regimens
Seizures
What are some adverse effects of Calcium Chanel Blockers?
Dizziness, somnolence, confusion, and ataxia.
Pedel edema.
What is the MOA of NMDA Antagonists?
Decreases postsynaptic depolarization
What is an example of a NMDA antagonist?
Ketamine
What role in therapy does ketamine have?
Acute pain opioid sparing regimens
Chronic pain
Mood disorders
What are some adverse effects of ketamine?
Confusion, delirium, dreamlike state, excitement, hallucinations, irrational behavior, and vivid imagery.
What adverse effect of NSAIDs is significant for COX-2 selective agents?
CV disease (myocardial infarction and stroke)
What major endogenous ligands to the mu receptors bind to?
Endorphin
What major endogenous ligands to kappa receptors bind to?
Dynorphin
What major endogenous ligands to delta receptors bind to?
Enkephalins
What are some examples of full mu agonists?
Codeine and morphine
Oxycodone, oxymorphone, hydrodocone, and hydromorphone
Methadone, fentanyl, meperidine
What are some examples of partial mu agonists?
Buprenorphine and Tramadol
What are some examples of mixed agonist/antagonists?
Buprenorphine and Nalbuphine
What are some full mu antagonists?
Naloxone, Methylnaltrexone, and Naltrexone
What are some additional properties of morphine?
Histamine release (itching/rash)
What are some additional properties of methadone?
NMDA receptor antagonism
What are some notable adverse effects of methadone?
QTc prolongation and drug interactions
What is methadone used for?
Chronic pain and opioid use disorder
What are some additional properties of fentanyl?
Serotonergic
What are some additional properties of meperidine?
Serotonergic and anticholinergic
What are some adverse effects of meperidine?
Serotonergic, anticholinergic, and neurotoxicity
What are some additional properties of tramadol?
Inhibits the re-uptake of serotonin and NE
What are some adverse effects of tramadol?
Serotonin syndrome and lowers seizure threshold.
What does the mnemonic “With seizures, I BITE my tongue” stand for?
Isoniazid, bupropion, imipenem/cilastatin, tramadol, enfluane.
What is the MOA of Naloxone?
Full mu competitive antagonist that acts centrally and peripherally.
What timeline is the duration of action of naloxone?
Short
What is the role in therapy for naloxone?
Acute opioid overdoses and toxicity.
What timeline is the duration of action of naltrexone?
Full mu competitive antagonist that acts centrally and peripherally.
What timeline is the duration of action of naltrexone?
Long
What is the role in therapy for naltrexone?
Opioid use disorder (OUD) and alcohol use disorder.
What is the MOA of methylnaltrexone?
Full mu competitive antagonist that acts peripherally.
What is the role in therapy of methylnaltraxone?
Opioid use constipation.
What is the MOA of Buprenorphine?
Partial/mixed mu-agonist that demonstrates a ceiling effect.
What is the role in therapy for buprenorphine?
Chronic pain and opioid use disorder.
What is the MOA of Nalbuphine?
Partial/mixed mu-antagonist.
What is the role in therapy of Nalbuphine?
Opioid-induced pruritis
What is Clonidine used for?
Treatment of opioid withdrawal